Hearing aid



FIG. 1 is a front and right side perspective view of hearing aid of the present invention;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a rear and left side perspective view thereof.

The alternating dash-dot lines represent the bounds of the claim, and the evenly spaced broken lines are included for the purpose of illustrating environment. None of the broken lines form a part of the claimed design. 

The ornamental design for a hearing aid, as shown and described. 